libio/libio.h

   1 /* Copyright (C) 1991-1995,1997-2006,2007,2009,2011 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Written by Per Bothner <bothner@cygnus.com>.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.
  19
  20    As a special exception, if you link the code in this file with
  21    files compiled with a GNU compiler to produce an executable,
  22    that does not cause the resulting executable to be covered by
  23    the GNU Lesser General Public License.  This exception does not
  24    however invalidate any other reasons why the executable file
  25    might be covered by the GNU Lesser General Public License.
  26    This exception applies to code released by its copyright holders
  27    in files containing the exception.  */
  28
  29 #ifndef _IO_STDIO_H
  30 #define _IO_STDIO_H
  31
  32 #include <_G_config.h>
  33 /* ALL of these should be defined in _G_config.h */
  34 #define _IO_pos_t _G_fpos_t /* obsolete */
  35 #define _IO_fpos_t _G_fpos_t
  36 #define _IO_fpos64_t _G_fpos64_t
  37 #define _IO_size_t _G_size_t
  38 #define _IO_ssize_t _G_ssize_t
  39 #define _IO_off_t _G_off_t
  40 #define _IO_off64_t _G_off64_t
  41 #define _IO_pid_t _G_pid_t
  42 #define _IO_uid_t _G_uid_t
  43 #define _IO_iconv_t _G_iconv_t
  44 #define _IO_HAVE_SYS_WAIT _G_HAVE_SYS_WAIT
  45 #define _IO_HAVE_ST_BLKSIZE _G_HAVE_ST_BLKSIZE
  46 #define _IO_BUFSIZ _G_BUFSIZ
  47 #define _IO_va_list _G_va_list
  48 #define _IO_wint_t _G_wint_t
  49
  50 #ifdef _G_NEED_STDARG_H
  51 /* This define avoids name pollution if we're using GNU stdarg.h */
  52 # define __need___va_list
  53 # include <stdarg.h>
  54 # ifdef __GNUC_VA_LIST
  55 #  undef _IO_va_list
  56 #  define _IO_va_list __gnuc_va_list
  57 # endif /* __GNUC_VA_LIST */
  58 #endif
  59
  60 #ifndef __P
  61 # if _G_HAVE_SYS_CDEFS
  62 #  include <sys/cdefs.h>
  63 # else
  64 #  ifdef __STDC__
  65 #   define __P(p) p
  66 #   define __PMT(p) p
  67 #  else
  68 #   define __P(p) ()
  69 #   define __PMT(p) ()
  70 #  endif
  71 # endif
  72 #endif /*!__P*/
  73
  74 /* For backward compatibility */
  75 #ifndef _PARAMS
  76 # define _PARAMS(protos) __P(protos)
  77 #endif /*!_PARAMS*/
  78
  79 #ifndef __STDC__
  80 # ifndef const
  81 #  define const
  82 # endif
  83 #endif
  84 #define _IO_UNIFIED_JUMPTABLES 1
  85 #ifndef _G_HAVE_PRINTF_FP
  86 # define _IO_USE_DTOA 1
  87 #endif
  88
  89 #ifndef EOF
  90 # define EOF (-1)
  91 #endif
  92 #ifndef NULL
  93 # if defined __GNUG__ && \
  94     (__GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 8))
  95 #  define NULL (__null)
  96 # else
  97 #  if !defined(__cplusplus)
  98 #   define NULL ((void*)0)
  99 #  else
 100 #   define NULL (0)
 101 #  endif
 102 # endif
 103 #endif
 104
 105 #define _IOS_INPUT      1
 106 #define _IOS_OUTPUT     2
 107 #define _IOS_ATEND      4
 108 #define _IOS_APPEND     8
 109 #define _IOS_TRUNC      16
 110 #define _IOS_NOCREATE   32
 111 #define _IOS_NOREPLACE  64
 112 #define _IOS_BIN        128
 113
 114 /* Magic numbers and bits for the _flags field.
 115    The magic numbers use the high-order bits of _flags;
 116    the remaining bits are available for variable flags.
 117    Note: The magic numbers must all be negative if stdio
 118    emulation is desired. */
 119
 120 #define _IO_MAGIC 0xFBAD0000 /* Magic number */
 121 #define _OLD_STDIO_MAGIC 0xFABC0000 /* Emulate old stdio. */
 122 #define _IO_MAGIC_MASK 0xFFFF0000
 123 #define _IO_USER_BUF 1 /* User owns buffer; don't delete it on close. */
 124 #define _IO_UNBUFFERED 2
 125 #define _IO_NO_READS 4 /* Reading not allowed */
 126 #define _IO_NO_WRITES 8 /* Writing not allowd */
 127 #define _IO_EOF_SEEN 0x10
 128 #define _IO_ERR_SEEN 0x20
 129 #define _IO_DELETE_DONT_CLOSE 0x40 /* Don't call close(_fileno) on cleanup. */
 130 #define _IO_LINKED 0x80 /* Set if linked (using _chain) to streambuf::_list_all.*/
 131 #define _IO_IN_BACKUP 0x100
 132 #define _IO_LINE_BUF 0x200
 133 #define _IO_TIED_PUT_GET 0x400 /* Set if put and get pointer logicly tied. */
 134 #define _IO_CURRENTLY_PUTTING 0x800
 135 #define _IO_IS_APPENDING 0x1000
 136 #define _IO_IS_FILEBUF 0x2000
 137 #define _IO_BAD_SEEN 0x4000
 138 #define _IO_USER_LOCK 0x8000
 139
 140 #define _IO_FLAGS2_MMAP 1
 141 #define _IO_FLAGS2_NOTCANCEL 2
 142 #ifdef _LIBC
 143 # define _IO_FLAGS2_FORTIFY 4
 144 #endif
 145 #define _IO_FLAGS2_USER_WBUF 8
 146 #ifdef _LIBC
 147 # define _IO_FLAGS2_SCANF_STD 16
 148 # define _IO_FLAGS2_NOCLOSE 32
 149 # define _IO_FLAGS2_CLOEXEC 64
 150 #endif
 151
 152 /* These are "formatting flags" matching the iostream fmtflags enum values. */
 153 #define _IO_SKIPWS 01
 154 #define _IO_LEFT 02
 155 #define _IO_RIGHT 04
 156 #define _IO_INTERNAL 010
 157 #define _IO_DEC 020
 158 #define _IO_OCT 040
 159 #define _IO_HEX 0100
 160 #define _IO_SHOWBASE 0200
 161 #define _IO_SHOWPOINT 0400
 162 #define _IO_UPPERCASE 01000
 163 #define _IO_SHOWPOS 02000
 164 #define _IO_SCIENTIFIC 04000
 165 #define _IO_FIXED 010000
 166 #define _IO_UNITBUF 020000
 167 #define _IO_STDIO 040000
 168 #define _IO_DONT_CLOSE 0100000
 169 #define _IO_BOOLALPHA 0200000
 170
 171
 172 struct _IO_jump_t;  struct _IO_FILE;
 173
 174 /* Handle lock.  */
 175 #ifdef _IO_MTSAFE_IO
 176 # if defined __GLIBC__ && __GLIBC__ >= 2
 177 #  include <bits/stdio-lock.h>
 178 # else
 179 /*# include <comthread.h>*/
 180 # endif
 181 #else
 182 typedef void _IO_lock_t;
 183 #endif
 184
 185
 186 /* A streammarker remembers a position in a buffer. */
 187
 188 struct _IO_marker {
 189   struct _IO_marker *_next;
 190   struct _IO_FILE *_sbuf;
 191   /* If _pos >= 0
 192  it points to _buf->Gbase()+_pos. FIXME comment */
 193   /* if _pos < 0, it points to _buf->eBptr()+_pos. FIXME comment */
 194   int _pos;
 195 #if 0
 196     void set_streampos(streampos sp) { _spos = sp; }
 197     void set_offset(int offset) { _pos = offset; _spos = (streampos)(-2); }
 198   public:
 199     streammarker(streambuf *sb);
 200     ~streammarker();
 201     int saving() { return  _spos == -2; }
 202     int delta(streammarker&);
 203     int delta();
 204 #endif
 205 };
 206
 207 /* This is the structure from the libstdc++ codecvt class.  */
 208 enum __codecvt_result
 209 {
 210   __codecvt_ok,
 211   __codecvt_partial,
 212   __codecvt_error,
 213   __codecvt_noconv
 214 };
 215
 216 #if defined _LIBC || defined _GLIBCPP_USE_WCHAR_T
 217 /* The order of the elements in the following struct must match the order
 218    of the virtual functions in the libstdc++ codecvt class.  */
 219 struct _IO_codecvt
 220 {
 221   void (*__codecvt_destr) (struct _IO_codecvt *);
 222   enum __codecvt_result (*__codecvt_do_out) (struct _IO_codecvt *,
 223                                              __mbstate_t *,
 224                                              const wchar_t *,
 225                                              const wchar_t *,
 226                                              const wchar_t **, char *,
 227                                              char *, char **);
 228   enum __codecvt_result (*__codecvt_do_unshift) (struct _IO_codecvt *,
 229                                                  __mbstate_t *, char *,
 230                                                  char *, char **);
 231   enum __codecvt_result (*__codecvt_do_in) (struct _IO_codecvt *,
 232                                             __mbstate_t *,
 233                                             const char *, const char *,
 234                                             const char **, wchar_t *,
 235                                             wchar_t *, wchar_t **);
 236   int (*__codecvt_do_encoding) (struct _IO_codecvt *);
 237   int (*__codecvt_do_always_noconv) (struct _IO_codecvt *);
 238   int (*__codecvt_do_length) (struct _IO_codecvt *, __mbstate_t *,
 239                               const char *, const char *, _IO_size_t);
 240   int (*__codecvt_do_max_length) (struct _IO_codecvt *);
 241
 242   _IO_iconv_t __cd_in;
 243   _IO_iconv_t __cd_out;
 244 };
 245
 246 /* Extra data for wide character streams.  */
 247 struct _IO_wide_data
 248 {
 249   wchar_t *_IO_read_ptr;        /* Current read pointer */
 250   wchar_t *_IO_read_end;        /* End of get area. */
 251   wchar_t *_IO_read_base;       /* Start of putback+get area. */
 252   wchar_t *_IO_write_base;      /* Start of put area. */
 253   wchar_t *_IO_write_ptr;       /* Current put pointer. */
 254   wchar_t *_IO_write_end;       /* End of put area. */
 255   wchar_t *_IO_buf_base;        /* Start of reserve area. */
 256   wchar_t *_IO_buf_end;         /* End of reserve area. */
 257   /* The following fields are used to support backing up and undo. */
 258   wchar_t *_IO_save_base;       /* Pointer to start of non-current get area. */
 259   wchar_t *_IO_backup_base;     /* Pointer to first valid character of
 260                                    backup area */
 261   wchar_t *_IO_save_end;        /* Pointer to end of non-current get area. */
 262
 263   __mbstate_t _IO_state;
 264   __mbstate_t _IO_last_state;
 265   struct _IO_codecvt _codecvt;
 266
 267   wchar_t _shortbuf[1];
 268
 269   const struct _IO_jump_t *_wide_vtable;
 270 };
 271 #endif
 272
 273 struct _IO_FILE {
 274   int _flags;           /* High-order word is _IO_MAGIC; rest is flags. */
 275 #define _IO_file_flags _flags
 276
 277   /* The following pointers correspond to the C++ streambuf protocol. */
 278   /* Note:  Tk uses the _IO_read_ptr and _IO_read_end fields directly. */
 279   char* _IO_read_ptr;   /* Current read pointer */
 280   char* _IO_read_end;   /* End of get area. */
 281   char* _IO_read_base;  /* Start of putback+get area. */
 282   char* _IO_write_base; /* Start of put area. */
 283   char* _IO_write_ptr;  /* Current put pointer. */
 284   char* _IO_write_end;  /* End of put area. */
 285   char* _IO_buf_base;   /* Start of reserve area. */
 286   char* _IO_buf_end;    /* End of reserve area. */
 287   /* The following fields are used to support backing up and undo. */
 288   char *_IO_save_base; /* Pointer to start of non-current get area. */
 289   char *_IO_backup_base;  /* Pointer to first valid character of backup area */
 290   char *_IO_save_end; /* Pointer to end of non-current get area. */
 291
 292   struct _IO_marker *_markers;
 293
 294   struct _IO_FILE *_chain;
 295
 296   int _fileno;
 297 #if 0
 298   int _blksize;
 299 #else
 300   int _flags2;
 301 #endif
 302   _IO_off_t _old_offset; /* This used to be _offset but it's too small.  */
 303
 304 #define __HAVE_COLUMN /* temporary */
 305   /* 1+column number of pbase(); 0 is unknown. */
 306   unsigned short _cur_column;
 307   signed char _vtable_offset;
 308   char _shortbuf[1];
 309
 310   /*  char* _save_gptr;  char* _save_egptr; */
 311
 312   _IO_lock_t *_lock;
 313 #ifdef _IO_USE_OLD_IO_FILE
 314 };
 315
 316 struct _IO_FILE_complete
 317 {
 318   struct _IO_FILE _file;
 319 #endif
 320 #if defined _G_IO_IO_FILE_VERSION && _G_IO_IO_FILE_VERSION == 0x20001
 321   _IO_off64_t _offset;
 322 # if defined _LIBC || defined _GLIBCPP_USE_WCHAR_T
 323   /* Wide character stream stuff.  */
 324   struct _IO_codecvt *_codecvt;
 325   struct _IO_wide_data *_wide_data;
 326   struct _IO_FILE *_freeres_list;
 327   void *_freeres_buf;
 328   size_t _freeres_size;
 329 # else
 330   void *__pad1;
 331   void *__pad2;
 332   void *__pad3;
 333   void *__pad4;
 334   size_t __pad5;
 335 # endif
 336   int _mode;
 337   /* Make sure we don't get into trouble again.  */
 338   char _unused2[15 * sizeof (int) - 4 * sizeof (void *) - sizeof (size_t)];
 339 #endif
 340 };
 341
 342 #ifndef __cplusplus
 343 typedef struct _IO_FILE _IO_FILE;
 344 #endif
 345
 346 struct _IO_FILE_plus;
 347
 348 extern struct _IO_FILE_plus _IO_2_1_stdin_;
 349 extern struct _IO_FILE_plus _IO_2_1_stdout_;
 350 extern struct _IO_FILE_plus _IO_2_1_stderr_;
 351 #ifndef _LIBC
 352 #define _IO_stdin ((_IO_FILE*)(&_IO_2_1_stdin_))
 353 #define _IO_stdout ((_IO_FILE*)(&_IO_2_1_stdout_))
 354 #define _IO_stderr ((_IO_FILE*)(&_IO_2_1_stderr_))
 355 #else
 356 extern _IO_FILE *_IO_stdin attribute_hidden;
 357 extern _IO_FILE *_IO_stdout attribute_hidden;
 358 extern _IO_FILE *_IO_stderr attribute_hidden;
 359 #endif
 360
 361
 362 /* Functions to do I/O and file management for a stream.  */
 363
 364 /* Read NBYTES bytes from COOKIE into a buffer pointed to by BUF.
 365    Return number of bytes read.  */
 366 typedef __ssize_t __io_read_fn (void *__cookie, char *__buf, size_t __nbytes);
 367
 368 /* Write N bytes pointed to by BUF to COOKIE.  Write all N bytes
 369    unless there is an error.  Return number of bytes written, or -1 if
 370    there is an error without writing anything.  If the file has been
 371    opened for append (__mode.__append set), then set the file pointer
 372    to the end of the file and then do the write; if not, just write at
 373    the current file pointer.  */
 374 typedef __ssize_t __io_write_fn (void *__cookie, __const char *__buf,
 375                                  size_t __n);
 376
 377 /* Move COOKIE's file position to *POS bytes from the
 378    beginning of the file (if W is SEEK_SET),
 379    the current position (if W is SEEK_CUR),
 380    or the end of the file (if W is SEEK_END).
 381    Set *POS to the new file position.
 382    Returns zero if successful, nonzero if not.  */
 383 typedef int __io_seek_fn (void *__cookie, _IO_off64_t *__pos, int __w);
 384
 385 /* Close COOKIE.  */
 386 typedef int __io_close_fn (void *__cookie);
 387
 388
 389 #ifdef _GNU_SOURCE
 390 /* User-visible names for the above.  */
 391 typedef __io_read_fn cookie_read_function_t;
 392 typedef __io_write_fn cookie_write_function_t;
 393 typedef __io_seek_fn cookie_seek_function_t;
 394 typedef __io_close_fn cookie_close_function_t;
 395
 396 /* The structure with the cookie function pointers.  */
 397 typedef struct
 398 {
 399   __io_read_fn *read;           /* Read bytes.  */
 400   __io_write_fn *write;         /* Write bytes.  */
 401   __io_seek_fn *seek;           /* Seek/tell file position.  */
 402   __io_close_fn *close;         /* Close file.  */
 403 } _IO_cookie_io_functions_t;
 404 typedef _IO_cookie_io_functions_t cookie_io_functions_t;
 405
 406 struct _IO_cookie_file;
 407
 408 /* Initialize one of those.  */
 409 extern void _IO_cookie_init (struct _IO_cookie_file *__cfile, int __read_write,
 410                              void *__cookie, _IO_cookie_io_functions_t __fns);
 411 #endif
 412
 413
 414 #ifdef __cplusplus
 415 extern "C" {
 416 #endif
 417
 418 extern int __underflow (_IO_FILE *);
 419 extern int __uflow (_IO_FILE *);
 420 extern int __overflow (_IO_FILE *, int);
 421 #if defined _LIBC || defined _GLIBCPP_USE_WCHAR_T
 422 extern _IO_wint_t __wunderflow (_IO_FILE *);
 423 extern _IO_wint_t __wuflow (_IO_FILE *);
 424 extern _IO_wint_t __woverflow (_IO_FILE *, _IO_wint_t);
 425 #endif
 426
 427 #if  __GNUC__ >= 3
 428 # define _IO_BE(expr, res) __builtin_expect ((expr), res)
 429 #else
 430 # define _IO_BE(expr, res) (expr)
 431 #endif
 432
 433 #define _IO_getc_unlocked(_fp) \
 434        (_IO_BE ((_fp)->_IO_read_ptr >= (_fp)->_IO_read_end, 0) \
 435         ? __uflow (_fp) : *(unsigned char *) (_fp)->_IO_read_ptr++)
 436 #define _IO_peekc_unlocked(_fp) \
 437        (_IO_BE ((_fp)->_IO_read_ptr >= (_fp)->_IO_read_end, 0) \
 438           && __underflow (_fp) == EOF ? EOF \
 439         : *(unsigned char *) (_fp)->_IO_read_ptr)
 440 #define _IO_putc_unlocked(_ch, _fp) \
 441    (_IO_BE ((_fp)->_IO_write_ptr >= (_fp)->_IO_write_end, 0) \
 442     ? __overflow (_fp, (unsigned char) (_ch)) \
 443     : (unsigned char) (*(_fp)->_IO_write_ptr++ = (_ch)))
 444
 445 #if defined _LIBC || defined _GLIBCPP_USE_WCHAR_T
 446 # define _IO_getwc_unlocked(_fp) \
 447   (_IO_BE ((_fp)->_wide_data == NULL                                    \
 448            || ((_fp)->_wide_data->_IO_read_ptr                          \
 449                >= (_fp)->_wide_data->_IO_read_end), 0)                  \
 450    ? __wuflow (_fp) : (_IO_wint_t) *(_fp)->_wide_data->_IO_read_ptr++)
 451 # define _IO_putwc_unlocked(_wch, _fp) \
 452   (_IO_BE ((_fp)->_wide_data == NULL                                    \
 453            || ((_fp)->_wide_data->_IO_write_ptr                         \
 454                >= (_fp)->_wide_data->_IO_write_end), 0)                 \
 455    ? __woverflow (_fp, _wch)                                            \
 456    : (_IO_wint_t) (*(_fp)->_wide_data->_IO_write_ptr++ = (_wch)))
 457 #endif
 458
 459 #define _IO_feof_unlocked(__fp) (((__fp)->_flags & _IO_EOF_SEEN) != 0)
 460 #define _IO_ferror_unlocked(__fp) (((__fp)->_flags & _IO_ERR_SEEN) != 0)
 461
 462 extern int _IO_getc (_IO_FILE *__fp);
 463 extern int _IO_putc (int __c, _IO_FILE *__fp);
 464 extern int _IO_feof (_IO_FILE *__fp) __THROW;
 465 extern int _IO_ferror (_IO_FILE *__fp) __THROW;
 466
 467 extern int _IO_peekc_locked (_IO_FILE *__fp);
 468
 469 /* This one is for Emacs. */
 470 #define _IO_PENDING_OUTPUT_COUNT(_fp)   \
 471         ((_fp)->_IO_write_ptr - (_fp)->_IO_write_base)
 472
 473 extern void _IO_flockfile (_IO_FILE *) __THROW;
 474 extern void _IO_funlockfile (_IO_FILE *) __THROW;
 475 extern int _IO_ftrylockfile (_IO_FILE *) __THROW;
 476
 477 #ifdef _IO_MTSAFE_IO
 478 # define _IO_peekc(_fp) _IO_peekc_locked (_fp)
 479 # define _IO_flockfile(_fp) \
 480   if (((_fp)->_flags & _IO_USER_LOCK) == 0) _IO_flockfile (_fp)
 481 # define _IO_funlockfile(_fp) \
 482   if (((_fp)->_flags & _IO_USER_LOCK) == 0) _IO_funlockfile (_fp)
 483 #else
 484 # define _IO_peekc(_fp) _IO_peekc_unlocked (_fp)
 485 # define _IO_flockfile(_fp) /**/
 486 # define _IO_funlockfile(_fp) /**/
 487 # define _IO_ftrylockfile(_fp) /**/
 488 # define _IO_cleanup_region_start(_fct, _fp) /**/
 489 # define _IO_cleanup_region_end(_Doit) /**/
 490 #endif /* !_IO_MTSAFE_IO */
 491
 492 extern int _IO_vfscanf (_IO_FILE * __restrict, const char * __restrict,
 493                         _IO_va_list, int *__restrict);
 494 extern int _IO_vfprintf (_IO_FILE *__restrict, const char *__restrict,
 495                          _IO_va_list);
 496 extern _IO_ssize_t _IO_padn (_IO_FILE *, int, _IO_ssize_t);
 497 extern _IO_size_t _IO_sgetn (_IO_FILE *, void *, _IO_size_t);
 498
 499 extern _IO_off64_t _IO_seekoff (_IO_FILE *, _IO_off64_t, int, int);
 500 extern _IO_off64_t _IO_seekpos (_IO_FILE *, _IO_off64_t, int);
 501
 502 extern void _IO_free_backup_area (_IO_FILE *) __THROW;
 503
 504 #if defined _LIBC || defined _GLIBCPP_USE_WCHAR_T
 505 extern _IO_wint_t _IO_getwc (_IO_FILE *__fp);
 506 extern _IO_wint_t _IO_putwc (wchar_t __wc, _IO_FILE *__fp);
 507 extern int _IO_fwide (_IO_FILE *__fp, int __mode) __THROW;
 508 # if __GNUC__ >= 2
 509 /* While compiling glibc we have to handle compatibility with very old
 510    versions.  */
 511 #  if defined _LIBC && defined SHARED
 512 #   include <shlib-compat.h>
 513 #   if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
 514 #    define _IO_fwide_maybe_incompatible \
 515   (__builtin_expect (&_IO_stdin_used == NULL, 0))
 516 extern const int _IO_stdin_used;
 517 weak_extern (_IO_stdin_used);
 518 #   endif
 519 #  endif
 520 #  ifndef _IO_fwide_maybe_incompatible
 521 #   define _IO_fwide_maybe_incompatible (0)
 522 #  endif
 523 /* A special optimized version of the function above.  It optimizes the
 524    case of initializing an unoriented byte stream.  */
 525 #  define _IO_fwide(__fp, __mode) \
 526   ({ int __result = (__mode);                                                 \
 527      if (__result < 0 && ! _IO_fwide_maybe_incompatible)                      \
 528        {                                                                      \
 529          if ((__fp)->_mode == 0)                                              \
 530            /* We know that all we have to do is to set the flag.  */          \
 531            (__fp)->_mode = -1;                                                \
 532          __result = (__fp)->_mode;                                            \
 533        }                                                                      \
 534      else if (__builtin_constant_p (__mode) && (__mode) == 0)                 \
 535        __result = _IO_fwide_maybe_incompatible ? -1 : (__fp)->_mode;          \
 536      else                                                                     \
 537        __result = _IO_fwide (__fp, __result);                                 \
 538      __result; })
 539 # endif
 540
 541 extern int _IO_vfwscanf (_IO_FILE * __restrict, const wchar_t * __restrict,
 542                          _IO_va_list, int *__restrict);
 543 extern int _IO_vfwprintf (_IO_FILE *__restrict, const wchar_t *__restrict,
 544                           _IO_va_list);
 545 extern _IO_ssize_t _IO_wpadn (_IO_FILE *, wint_t, _IO_ssize_t);
 546 extern void _IO_free_wbackup_area (_IO_FILE *) __THROW;
 547 #endif
 548
 549 #ifdef __LDBL_COMPAT
 550 # include <bits/libio-ldbl.h>
 551 #endif
 552
 553 #ifdef __cplusplus
 554 }
 555 #endif
 556
 557 #endif /* _IO_STDIO_H */